This spare spiral that Constantin Brancusi traced to capture the likeness of writer James Joyce describes the sort of journey involved in what Joyce called the “sedentary trade”: using one’s life as the material for one’s work, each working and wandering into and out of the other.

This purposive wandering was also the origin of theoretical inquiry. The art world has developed a studied avoidance of theory, rationalized by claims that theory as we know it has died. Art school celebrates.

A recent article by Eyal Weizman in Frieze magazine notes that the varieties of theory that art students have learned to loathe are the classroom texts and bedtime reading of top performers in the postmodern military machine. Weizman details the ways in which the Israeli armed forces have put their attentive readings in late 20th and early 21st century critical theory into practice with an efficacy and inventiveness that would make any art school theory professor jealous.

He cites Brigadier General Aviv Kokhavi, who led the Israeli attack on Nablus in 2002, describing that operation as “inverse geometry . . . the reorganization of the urban syntax by means of a series of micro-tactical actions.”

How does theory get here? Is this where it is bound to stay?

“From the Greek words referring to sight or seeing,” writes art historian Donald Preziosi, “the ‘theory’ of anything may be understood to be a particular view that unifies in some fundamental sense a wide variety of disparate phenomena.” The term “theory” connotes a tradition of careful observation and engagement and, crucially, a viewing — an imaging — of phenomena in a manner that permits the construction of a new constellation of their relationships. This provisional model guides an engagement with the world in a way that affords possibilities for the production of knowledge, forms of practice, ways of being in the world that were not imagined in advance of the outset of a particular theoretical endeavor.

Theory appears first to appear in ancient Greek references to theoria, a pilgrimage undertaken to a foreign place to see a religious festival or to consult an oracle. The theoros is the individual who makes such a journey on his or her community’s behalf.

Plato’s Republic begins with an account of such a journey. Socrates says: “I walked down to the Piraeus yesterday with Glaucon, the son of Ariston, to make my prayers to the goddess. As this was the first celebration of her festival, I wished also to see how the ceremony would be conducted. The Thracians, I thought, made as fine a show in the procession as our own people, though they did well enough. The prayers and the spectacle were over, and we were leaving to go back to the city, when from some way off Polemarchus, the son of Cephalus, caught sight of us . . .”